Promotion of normal healing of bone defects under estrogen deficiency by implantation of beta‐tricalcium phosphate composed of rod‐shaped particles

We compared the healing of bone defects in ovariectomized rats implanted with beta‐tricalcium phosphate (β‐TCP) composed of rod‐shaped particles, which were prepared using the applied hydrothermal method (HTCP), and that of bone defects implanted with conventional β‐TCP composed of globular‐shaped particles (CTCP), which were prepared by normal sintering. Eight‐week‐old female Wistar rats were ovariectomized, and 2 weeks after the operation, 0.5‐ to 0.6‐mm diameter spherical granules of each ceramic were implanted in a bone defect created in the distal end of the femur. Four, 8, and 12 weeks after implantation, the amount of newly formed bone implanted with HTCP was significantly larger than that implanted with CTCP and was equivalent to that in non‐ovariectomized sham‐operated rats. Without implantation, spontaneous repair of the trabecular bone was barely observed. The physiological structure of the trabecular network was maintained in the region implanted with HTCP, but that in the region implanted with CTCP was severely destroyed. Gene expression microarray analysis revealed that the expression of genes involved in interferon signaling pathways was upregulated in osteoclasts cultured on HTCP compared with that cultured on CTCP. Our results suggest that the microstructure of β‐TCP affected the biological behavior of osteoclasts and regulated local bone metabolism. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:189–196, 2014.     

Distribution of nerves containing vasoactive intestinal polypeptide-like immunoreactivity in rats with congenital aganglionosis of the colon

The distribution of nerves containing vasoactive intestinal polypeptide-like immunoreactivity was examined immunohistochemically in whole-mount specimens of the colons of mutant rats, which completely lacked intramural nerve cells in the colon, and of their normal littermates. In the aganglionic colon, greatly diminished numbers of vasoactive intestinal polypeptide-like immunoreactive nerve fibers were found in the circular muscle layer, lamina propria of the mucosa, and in the submucosa. In the intermuscular space of the aganglionic colon, unlike the pattern of the normal Auerbach's plexus, vasoactive intestinal polypeptide-like immunoreactive nerve fibers were arranged in an irregular, coarse network. These findings suggest the existence of extrinsic nerves containing vasoactive intestinal polypeptide in the aganglionic colon of the hereditary aganglionic rat.     

Performance characteristics of updated INNO-LiPA assays for molecular typing of human leukocyte antigen A (HLA-A), HLA-B, and HLA-DQB1 alleles

We carried out a multicenter performance evaluation of three new DNA-based human leukocyte antigen (HLA) typing assays: INNO-LiPA HLA-A Update, INNO-LiPA HLA-B Update, and INNO-LiPA HLA-DQB1 Update. After optimization, the accuracy rates were all 100%, and the final observed resolutions were 99.4, 92.4, and 85.6%, respectively. These rapid and easy-to-perform assays yielded results fully concordant with other DNA-based tissue typing tests.